Circuit simulation is widely used to test circuit designs prior to the actual implementation of the circuit in hardware. One circuit behavior that is important to emulate in simulators is the effect of jitter. For the purposes of the present discussion, jitter is defined to be the difference between the signal's expected threshold crossing time and the actual crossing time. Jitter can be the result of a number of effects in a circuit including imperfections in the clock signals and inter-symbol-interference. To analyze the effects of jitter on a circuit, a mechanism for injecting the jitter into an input or output signal to or from a component in the circuit is needed. Jitter injection to continuous signals has important applications in system analyses and measurements. For example, jitter is injected into input signals to study system tolerances to timing impairments. In system level designs, jitter is injected to outputs of functional blocks when simulating full system performances to simulate the jitter introduced by that functional block. A complex system can be studied by allowing one or more functional blocks to inject jitter into the signals being processed by the blocks.